Forming a gate contact in the active area

ABSTRACT

A method of making a semiconductor device includes patterning a fin in a substrate; forming a gate between source/drain regions over the substrate, the gate having a dielectric spacer along a sidewall; removing a portion of the dielectric spacer and filling with a metal oxide to form a spacer having a first spacer portion and a second spacer portion; forming a source/drain contact over at least one of the source/drain regions; recessing the source/drain contact and forming a via contact over the source/drain contact; and forming a gate contact over the gate, the gate contact having a first gate contact portion contacting the gate and a second gate contact portion positioned over the first gate contact portion; wherein the first spacer portion isolates the first gate contact portion from the source/drain contact, and the second spacer portion isolates the second gate contact portion from the source/drain contact.

BACKGROUND

The present invention relates to metal-oxide-semiconductor field-effecttransistors (MOSFET), and more specifically, to gate contacts inMOSFETs.

The MOSFET is a transistor used for amplifying or switching electronicsignals. The MOSFET has a source, a drain, and a metal oxide gateelectrode. The metal gate is electrically insulated from the mainsemiconductor n-channel or p-channel by a layer of insulating material,for example, silicon dioxide or glass, which makes the input resistanceof the MOSFET relatively high. The gate voltage controls whether thepath from drain to source is an open circuit (“off”) or a resistive path(“on”).

Generally, the gate contact (also called the CB) is formed over shallowtrench isolation (STI) regions to avoid shorting between the gatecontact and the source/drain contact (also called the TS). However,placing the gate contact over the active area (also called the RX), orthe semiconductor regions where the source/drain regions are formed, maybe beneficial for increasing the integration density and reduce devicescaling.

SUMMARY

According to an embodiment of the present invention, a method of makinga semiconductor device includes patterning a fin in a substrate; forminga gate between source/drain regions over the substrate, the gate havinga dielectric spacer along a sidewall; removing a portion of thedielectric spacer and filling with a metal oxide to form a spacer havinga first spacer portion and a second spacer portion; forming asource/drain contact over at least one of the source/drain regions;recessing the source/drain contact and forming a via contact over thesource/drain contact; and forming a gate contact over the gate, the gatecontact having a first gate contact portion contacting the gate and asecond gate contact portion positioned over the first gate contactportion; wherein the first spacer portion isolates the first gatecontact portion from the source/drain contact, and the second spacerportion isolates the second gate contact portion from the source/draincontact.

In another embodiment, a method of making a semiconductor deviceincludes patterning a fin in a substrate; forming a gate betweensource/drain regions over the substrate, the gate having a dielectricspacer along a sidewall; removing a portion of the dielectric spacer andfilling with a metal oxide to form a spacer, the spacer having a firstspacer portion and a second spacer portion; recessing the gate anddepositing a dielectric cap over the gate; forming a source/draincontact over at least one of the source/drain regions, the source/draincontact contacting the spacer and the dielectric spacer; forming a viacontact over the source/drain contact; and removing the dielectric capand forming a gate contact over the gate, the gate contact having afirst gate contact portion contacting the gate and a second gate contactportion positioned over the first gate contact portion; wherein thefirst spacer portion isolates the first gate contact portion from thesource/drain contact, and the second spacer portion isolates the secondgate contact portion from the source/drain contact.

Yet, in another embodiment, a semiconductor device includes a finpatterned in a substrate; a gate contact disposed over a gate positionedover the substrate, the gate contact having a first gate contact portioncontacting the gate and a second gate contact portion positioned overthe first portion; a source/drain contact disposed over a source/drainregion positioned over the substrate; and a spacer between thesource/drain contact and the gate contact, the spacer having a firstspacer portion that isolates the first gate contact portion from thesource/drain contact and a second spacer portion that isolates thesecond gate contact portion from the source/drain contact.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter which is regarded as the invention is particularlypointed out and distinctly claimed in the claims at the conclusion ofthe specification. The forgoing and other features, and advantages ofthe invention are apparent from the following detailed description takenin conjunction with the accompanying drawings in which:

FIGS. 1A-1C illustrate a comparative example of a semiconductor devicewith a gate contact over the active area, in which;

FIG. 1A is a top view of the semiconductor device; and

FIGS. 1B and 1C are cross-sectional side views through the XX′ and YY′axes, respectively, of FIG. 1A;

FIGS. 2A-2C illustrate an exemplary semiconductor device according toembodiments of the present invention, in which:

FIG. 2A is a top view of the semiconductor device; and

FIGS. 2B and 2C are cross-sectional side views through the XX′ and YY′axes, respectively, of FIG. 2A;

FIGS. 3A-13B illustrate an exemplary method of making the semiconductordevice shown in FIGS. 2A-2C according to embodiments of the presentinvention, in which:

FIG. 3A illustrates a cross-sectional side view through the XX′ axis ofFIG. 2A showing metal gates over fins before forming a gate contact;

FIG. 3B is a cross-sectional side view through the XX′ axis afterrecessing the gate dielectric spacers;

FIG. 4A is a cross-sectional side view through the XX′ axis afterdepositing a conformal metal oxide layer to fill the gate spacerrecesses;

FIG. 4B is a cross-sectional side view through the XX′ axis afteretching back the metal oxide layer to form the spacers;

FIG. 5A is a cross-sectional side view through the XX′ axis afterrecessing back the metal gates;

FIG. 5B is a cross-sectional side view through the XX′ axis afterdepositing a dielectric cap over the metal gates;

FIG. 6A is a cross-sectional side view through the XX′ axis afterforming source/drain contacts;

FIG. 6B is a cross-sectional side view through the XX′ axis afterrecessing back the source/drain contacts;

FIG. 7 is a cross-sectional side view through the XX′ axis afterdepositing a blanket inter-level dielectric (ILD) oxide layer;

FIGS. 8A and 8B are cross-sectional side views through the XX′ and YY′axes, respectively, of FIG. 2A, after depositing and patterning alithographic patterning layer;

FIGS. 9A and 9B are cross-sectional side views through the XX′ and YY′axes, respectively, after etching through the ILD layer to form a viacontact pattern;

FIGS. 10A and 10B are cross-sectional side views through the XX′ and YY′axes, respectively, after depositing and patterning another lithographicpatterning stack;

FIGS. 11A and 11B are cross-sectional side views through the XX′ and YY′axes, respectively, after etching through the ILD layer to form a gatecontact pattern;

FIGS. 12A and 12B are cross-sectional side views through the XX′ and YY′axes, respectively, after removing the dielectric cap over the gates;and

FIGS. 13A and 13B are cross-sectional side views through the XX′ and YY′axes, respectively, after removing the patterning stack and filling thegate contact and the via contacts with a conductive metal.

DETAILED DESCRIPTION

One method for placing a gate contact over the active area of asemiconductor device involves forming a deep recess for the source/draincontact. However, deep recesses in the source/drain contact make it morechallenging to align the via contact over the source/drain contact.Further, such designs may induce shorting between the gate contact andthe source/drain contact, as shown in FIGS. 1A-1C below.

Accordingly, embodiments of the present invention provide methods ofmaking semiconductor devices with gate contacts over active areas usingshallow source/drain contacts. Shallow source/drain contacts enableaccessible via contact alignment. The gate contact is isolated from thesource/drain contacts by a spacer with two portions. A first portionisolates the gate conductor from the source/drain contacts, and a secondportion isolates the upper gate contact portion from the source/draincontacts. Embodiments of the inventive semiconductor devices and methodsprovide advantages of forming gate contacts over active areas that avoidgate contact to source/drain contact shorting and allow for easier viacontact formation over the source/drain contact. It is noted that likereference numerals refer to like elements across different embodiments.

The following definitions and abbreviations are to be used for theinterpretation of the claims and the specification. As used herein, theterms “comprises,” “comprising,” “includes,” “including,” “has,”“having,” “contains” or “containing,” or any other variation thereof,are intended to cover a non-exclusive inclusion. For example, acomposition, a mixture, process, method, article, or apparatus thatcomprises a list of elements is not necessarily limited to only thoseelements but can include other elements not expressly listed or inherentto such composition, mixture, process, method, article, or apparatus.

As used herein, the articles “a” and “an” preceding an element orcomponent are intended to be nonrestrictive regarding the number ofinstances (i.e. occurrences) of the element or component. Therefore, “a”or “an” should be read to include one or at least one, and the singularword form of the element or component also includes the plural unlessthe number is obviously meant to be singular.

As used herein, the terms “invention” or “present invention” arenon-limiting terms and not intended to refer to any single aspect of theparticular invention but encompass all possible aspects as described inthe specification and the claims.

As used herein, the term “about” modifying the quantity of aningredient, component, or reactant of the invention employed refers tovariation in the numerical quantity that can occur, for example, throughtypical measuring and liquid handling procedures used for makingconcentrates or solutions. Furthermore, variation can occur frominadvertent error in measuring procedures, differences in themanufacture, source, or purity of the ingredients employed to make thecompositions or carry out the methods, and the like. In one aspect, theterm “about” means within 10% of the reported numerical value. Inanother aspect, the term “about” means within 5% of the reportednumerical value. Yet, in another aspect, the term “about” means within10, 9, 8, 7, 6, 5, 4, 3, 2, or 1% of the reported numerical value.

Turning now to the Figures, FIGS. 1A-1C illustrate a comparative exampleof a semiconductor device with a gate contact over the active area. FIG.1A is a top view of the semiconductor device. FIGS. 1B and 1C arecross-sectional side views through the XX′ and YY′ axes, respectively,of FIG. 1A. For simplicity, FIG. 1A does not show the ILD layer 110 orSTI regions 162 shown in FIGS. 1B and 1C.

Fins 161 are patterned in a substrate 160 including STI regions 162.Metal gates 106 surrounded by dielectric spacers 150 are disposed overthe fin 161. In FIG. 1A, the metal gates 106 are indicated by opendashed boxes 101, which are beneath dielectric caps 180 as shown inFIGS. 1B and 1C. Source/drain contacts 104 are over source/drain regions140. A gate contact 103 is disposed over the metal gate 106. Viacontacts 102 forming the active area are disposed over the source/draincontacts 104 as shown in FIG. 1C. The source/drain contacts 104 areformed in a deep recess (R1) below the level of the dielectric spacer150 material to avoid contact (and shorting) with the source/draincontact 104. The deep recess (R1) increases the length (L1) of the viacontact 102. However, even with the source/drain contact 104 positionedwithin the deep recess (R1), shorting may still occur in region 170shown in FIG. 1B due to the relatively short distance between thesource/drain contact 104 and the gate contact 103.

Accordingly, FIGS. 2A-2C illustrate an exemplary semiconductor deviceaccording to embodiments of the present invention, which alleviate therisk of shorting. FIGS. 2A-2C are described in further detail in FIGS.3A-13B.

FIG. 2A is a top view of the semiconductor device. FIGS. 2B and 2C arecross-sectional side views through the XX′ and YY′ axes, respectively,of FIG. 2A. For simplicity, FIG. 2A does not show the ILD layer 210 orSTI regions 262 shown in FIGS. 2B and 2C.

Metal gates 206 surrounded by dielectric spacers 250 are formed overfins 261 patterned in a substrate 260. In FIG. 2A, the metal gates 206are indicated by open dashed boxes 201, which are beneath dielectriccaps 510. Source/drain contacts 204 are formed over source/drain regions240. A gate contact 203 is formed over the metal gate 206. Via contacts202 forming the active area are formed over the source/drain contacts204. Spacers 251 formed of an insulating metal oxide material arepositioned between the gate contact 203 and the source/drain contact204. The spacers 251 prevent shorting in the region 270 between the gatecontact 203 and the source/drain contact 204. The source/drain contacts204 are formed in a shallow recess (R2), which means that the length(L2) of the contact via 202 is shorter and more easily aligned with thesource/drain contact to form the active area. At least a portion of thevia contact 202 is more narrow than the source/drain contact 204.

FIGS. 3A-13B illustrate an exemplary method of making the semiconductordevice shown in FIGS. 2A-2C according to embodiments of the presentinvention. FIG. 3A illustrates a cross-sectional side view through theXX′ axis of FIG. 2A. FIG. 3A shows metal gates 206 disposed over fins261 before forming the gate contact 203. The fins 261 are patterned in asubstrate 260. Non-limiting examples of suitable substrate 260 materialsinclude silicon, silicon dioxide, aluminum oxide, sapphire, germanium,gallium arsenide, an alloy of silicon and germanium, indium phosphide,or any combination thereof. Other examples of suitable substratesinclude silicon-on-insulator (SOI) substrates with buried oxide (BOX)layers. The thickness of the substrate 260 is not intended to belimited. In one aspect, the thickness of the substrate 260 is in a rangefrom about 10 micrometers (μm) to about 1 millimeter (mm). In anotheraspect, the thickness of the substrate 260 is in a range from about 500μm to about 800 μm.

A STI process is performed to form the STI regions 262. The STI regions262 are isolation regions formed by etching trenches in the substrate260 and then filling the trenches with, for example, silicon oxide.Alternatively, the trenches may be lined with a silicon oxide linerformed by a thermal oxidation process and then filled with additionalsilicon oxide or another material.

To form the metal gates 206, initially, “dummy gates” (not shown) areformed over the fins 261. The dummy gates are filled with a suitablereplacement gate material, for example, amorphous silicon (polysilicon).A hard mask material, for example, silicon nitride (SiN), SiOCN, orSiBCN, is deposited over the dummy gates. An etching process, forexample, reactive ion etching (RIE) is performed to form dielectricspacers 250 surrounding the dummy gates, along the gate sidewall. Thedielectric spacer material is deposited by a deposition process, forexample, chemical vapor deposition (CVD) or physical vapor deposition(PVD). The thickness of the dielectric spacers 250 is not intended to belimited. In one aspect, the thickness of the dielectric spacers 250 isin a range from about 3 nanometers (nm) to about 30 nm. In anotheraspect, the thickness of the dielectric spacers 250 is in a range fromabout 5 nm to about 10 nm.

Source/drain regions 240 are formed by performing an epitaxial growthprocess over the fin 261. The epitaxial growth process deposits acrystalline material layer onto the crystalline substrate 260 beneath.The underlying substrate 260 acts as a seed crystal. Epitaxial layersmay be grown from gaseous or liquid precursors. Epitaxial silicon may begrown using vapor-phase epitaxy (VPE), molecular-beam epitaxy (MBE),liquid-phase epitaxy (LPE), or other suitable process. The epitaxialsilicon may be doped during deposition by adding a dopant or impurity.The silicon may be doped with an n-type dopant (e.g., phosphorus) or ap-type dopant (e.g., boron), depending on the type of transistor.

The thickness of the source/drain regions 240 is not intended to belimited. In one aspect, the thickness of the source/drain regions 240 isin a range from about 10 nm to about 80 nm. In another aspect, thethickness of the source/drain regions 240 is in a range from about 15 nmto about 30 nm.

The ILD layer 210 is formed by depositing a blanket layer of a low-kdielectric oxide material around the dummy gates within the dielectricspacers 250. Non-limiting examples of suitable low-k dielectricmaterials include a spin-on-glass, a flowable oxide, a high densityplasma oxide, borophosphosilicate glass (BPSG), or any combinationthereof. The ILD layer 210 material is deposited by a suitabledeposition process, including, but not limited to CVD, PVD, plasmaenhanced CVD, atomic layer deposition (ALD), evaporation, chemicalsolution deposition, or like processes.

The replacement gate material is removed from the dummy gates andreplaced with conductive gate materials to form the metal gates 206. Ahigh-k dielectric material may be deposited into the dummy gates to forma high-k liner. The high-k dielectric material may be a dielectricmaterial having a dielectric constant, for example, greater than 4.0,7.0, or 10.0. Non-limiting examples of suitable materials for the high-kdielectric material include oxides, nitrides, oxynitrides, silicates(e.g., metal silicates), aluminates, titanates, nitrides, or anycombination thereof. Other non-limiting examples of suitable high-kdielectric materials include HfO₂, ZrO₂, Al₂O₃, TiO2, La₂O₃, SrTiO₃,LaAlO₃, Y₂O₃, a pervoskite oxide, or any combination thereof. The high-kdielectric material layer may be formed by known deposition processes,for example, CVD, plasma-enhanced chemical vapor deposition (PECVD),ALD, evaporation, PVD, chemical solution deposition, or other likeprocesses. The thickness of the high-k dielectric material may varydepending on the deposition process as well as the composition andnumber of high-k dielectric materials used. The high-k dielectricmaterial layer may have a thickness in a range from about 0.5 to about20 nm.

A conductive gate metal is deposited over the high-k dielectricmaterial. Non-limiting examples of suitable conductive metals includealuminum (Al), platinum (Pt), gold (Au), tungsten (W), titanium (Ti), orany combination thereof. The conductive metal may be deposited by aknown deposition process, for example, CVD, PECVD, PVD, plating, thermalor e-beam evaporation, and sputtering. A planarization process, forexample, chemical mechanical planarization (CMP), is performed to polishthe surface of the conductive gate metal.

FIG. 3B is a cross-sectional side view after recessing the dielectricspacers 250. The spacer recesses 301 may be formed using a dry etchingprocess, for example, RIE, to remove a portion of the dielectric spacer250 material on opposing sides of the metal gates 206. The spacerrecesses may be recessed to a depth 302 that may generally vary. In oneaspect, the spacers 250 are recessed to a depth 302 in a range fromabout 5 nm to about 70 nm. In another aspect, the spacers 250 arerecessed to a depth 302 in a range from about 15 nm to about 30 nm.

FIG. 4A is a cross-sectional side view after depositing a conformalmetal oxide layer to fill the gate spacer recesses 301 and form thespacers 251, as shown in FIG. 4B below. The metal oxide material is aninsulating material and may be formed by an ALD process. Examples ofhigh-k materials include, but are not limited to, metal oxides such ashafnium oxide, hafnium silicon oxide, hafnium silicon oxynitride,lanthanum oxide, lanthanum aluminum oxide, zirconium oxide, zirconiumsilicon oxide, zirconium silicon oxynitride, tantalum oxide, titaniumoxide, barium strontium titanium oxide, barium titanium oxide, strontiumtitanium oxide, yttrium oxide, aluminum oxide, lead scandium tantalumoxide, and lead zinc niobate. The high-k may further include dopantssuch as lanthanum, aluminum.

The spacers 251 can be deposited by, for example, atomic layerdeposition (ALD), molecular layer deposition (MLD), chemical vapordeposition (CVD), low-pressure chemical vapor deposition (LPCVD), plasmaenhanced chemical vapor deposition (PECVD), limited reaction processingCVD (LRPCVD), or any other suitable processing.

FIG. 4B is a cross-sectional side view through the XX′ axis afteretching back the metal oxide layer to form the spacers 251. The spacerheight 401 is defined by the spacer recesses 301 as described above inFIG. 3B. Thus, the spacer heights 401 are defined by the depth of thespacer recesses 301 shown in FIG. 3B. An isotropic etching process maybe used to remove the metal oxide layer over the ILD layer 210.Isotropic etching processes are chemical etching processes that utilizea chemical etchant. Non-limiting examples of suitable isotropic etchantsinclude hydrofluoric acid (HF), hydrofluoric nitric acid (HNA), andphosphoric acid. The spacers 251 have a first spacer portion 252 and asecond spacer portion 253.

FIG. 5A is a cross-sectional side view after recessing back the metalgates 206 to form metal gate recesses 501. The metal gate recesses 501are formed by a dry etching process, for example, RIE. The metal gates206 are recessed to a level that is below the spacers 251. The spacer251 is above the metal gate recesses 501.

FIG. 5B is a cross-sectional side view after depositing a dielectric cap510 over the metal gates 206 and within the metal gate recesses 501. Thespacers 251 enable the dielectric cap 510 to be self-aligned over themetal gates 206. At least a portion of the dielectric cap 510 is belowthe spacers 251. Further, at least a portion of the dielectric cap 510is between the spacer 251 and the metal gate 206. The dielectric cap 510may be any suitable dielectric material and may be the same or differentthan the dielectric spacers 250. Non-limiting examples of suitablematerials for the dielectric cap 510 include SiN, SiOCN, SiBCN, or anycombination thereof. A planarization process is performed to polish thesurface of the dielectric cap 510.

FIG. 6A is a cross-sectional side view after forming source/draincontacts 204. The ILD layer 210 material over the source/drain regions240 is removed. A dry etching process, for example, reacting ion etching(RIE) may be used. The ILD layer 210 material is replaced with aconductive metal to form the source/drain contacts 204. Non-limitingexamples of suitable conductive metals include Al, Pt, Au, W, Ti, or anycombination thereof. The conductive metal may be deposited by a knowndeposition process, for example, CVD, PECVD, PVD, plating, thermal ore-beam evaporation, or sputtering.

FIG. 6B is a cross-sectional side view after recessing back thesource/drain contacts 204. The recessing is performed by a dry etchingprocess, for example, RIE. The source/drain contacts 204 are recessed toa shallow depth 601 that may generally vary. In one aspect, the shallowdepth 601 is in a range from about 5 nm to about 40 nm. In anotheraspect, the shallow depth 601 is in a range from about 15 nm to about 30nm.

FIG. 7 is a cross-sectional side view after depositing an additionalblanket ILD layer 210. The additional blanket oxide layer 210 may be thesame (shown) or different (not shown) than the ILD layer 210 that usedafter forming the dummy gates (see FIGS. 3A and 3B above).

FIGS. 8A and 8B are cross-sectional side views through the XX′ and YY′axes, respectively, of FIG. 2A after depositing and patterning alithographic patterning layer 801 over the structure formed in FIG. 7.The lithographic patterning layer 801 may be a stack or a single layer.For example, the lithographic patterning layer 801 may be an organicplanarizing layer (OPL) or a photoresist. The lithographic patterninglayer 801 is patterned over the source/drain contacts 204 as shown inFIG. 8B.

FIGS. 9A and 9B are cross-sectional side views through the XX′ and YY′axes, respectively, after etching the pattern through the ILD layer 210to form a via contact pattern 901. Etching is performed down to thesource/drain contacts 204. The etching process may a dry etchingprocess, for example, RIE. Because the source/drain contacts 204 arerecessed to the shallow depth 601, the via contact patterns 901 definingthe via contacts 202 (described in FIG. 13B below) have a shorter depth910 to reach the source/drain contacts 204. In one aspect, the depth 910of the via contact patterns 901 is in a range from about 30 nm to about150 nm. In another aspect, the depth 910 of the via contact patterns 901is in a range from about 50 nm to about 80 nm.

FIGS. 10A and 10B are cross-sectional side views through the XX′ and YY′axes, respectively, after depositing and patterning another lithographicpatterning layer 1001. The lithographic patterning layer 901 may be astack or a single layer. For example, the lithographic patterning layer901 may be an OPL or a photoresist. The lithographic patterning layer901 is patterned over the metal gate 206 as shown in FIG. 10A.

FIGS. 11A and 11B are cross-sectional side views through the XX′ and YY′axes, respectively, after etching through the ILD layer 210 to form aninitial gate contact pattern 1101. A timed dry etching process, forexample, RIE is performed to etch through the ILD layer 210 down to thelevel of the dielectric cap 510. The etching process is timed to notpenetrate the dielectric cap 510 or the spacers 251. The etching processis a selective etching process. In some embodiments, the ILD 210 issilicon oxide, the dielectric cap 510 is silicon nitride, and thespacers 251 are hafnium oxide or aluminum oxide.

FIGS. 12A and 12B are cross-sectional side views through the XX′ and YY′axes, respectively, after selectively removing the dielectric cap 510over the metal gate 206 to form a final gate contact pattern 1211. A dryetching process, for example, RIE, that is selective to (will notpenetrate) the spacer 251 material or the ILD layer 210 material isperformed to remove the dielectric cap 510 material. The region 1201shows that the spacer 251 provides sufficient space between the regiondirectly over the metal gate 206 (which will be the gate contact 203(see FIG. 13A)) and the source/drain contact 204 to prevent shorting.

The gate contact pattern 1211 includes a first gate contact portion 1210and a second gate contact portion 1211. The first gate contact portion1210 is directly over and contacts the metal gate 206. The second gatecontact portion 1211 is over the first gate contact portion 1210. Thesecond gate contact portion 1211 is wider than the first gate contactportion 1210. At least a portion of the second gate contact portion 1211is directly over at least one spacer 251.

FIGS. 13A and 13B are cross-sectional side views through the XX′ and YY′axes, respectively, after removing the patterning stack 901 and fillingwith a conductive metal to form the gate contact 203 and the viacontacts 202. The conductive metal may be the same or different for thegate contact 203 and the via contacts 202. Non-limiting examples ofsuitable conductive metals include Al, Pt, Au, W, Ti, or any combinationthereof. At least a portion of the via contacts 202 is more narrow thanthe source/drain contacts 204.

The gate contact 203 includes a first gate contact portion 1310 and asecond gate contact portion 1311. The first gate contact portion 1310 isdirectly over and contacts the metal gate 206. The second gate contactportion 1311 is over the first gate contact portion 1310. The secondgate contact portion 1311 is wider than the first gate contact portion1310. At least a portion of the second gate contact portion 1311 isdirectly over at least one of the spacers 251.

The spacer 251 is between the source/drain contact 204 and the gatecontact 203. The first spacer portion 252 isolates the first gatecontact portion 1310 from the source/drain contact 204. The secondspacer portion 253 isolates the second gate contact portion 1311 fromthe source/drain contact.

As described above, embodiments of the present invention provide methodsof making semiconductor devices with gate contacts over active areasusing shallow source/drain contacts. Shallow source/drain contactsenable accessible via contact alignment. The gate contact is isolatedfrom the source/drain contacts by a spacer with two portions. A firstportion isolates the gate conductor from the source/drain contact, and asecond portion isolates the gate contact from the source/drain contact.Embodiments of the inventive semiconductor devices and methods provideadvantages of providing gate contacts over active areas that avoid gatecontact to source/drain contact shorting and allow for easier viacontact formation over the source/drain contact.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, element components,and/or groups thereof.

The corresponding structures, materials, acts, and equivalents of allmeans or step plus function elements in the claims below are intended toinclude any structure, material, or act for performing the function incombination with other claimed elements as specifically claimed. Thedescription of the present invention has been presented for purposes ofillustration and description, but is not intended to be exhaustive orlimited to the invention in the form disclosed. Many modifications andvariations will be apparent to those of ordinary skill in the artwithout departing from the scope and spirit of the invention. Theembodiment was chosen and described in order to best explain theprinciples of the invention and the practical application, and to enableothers of ordinary skill in the art to understand the invention forvarious embodiments with various modifications as are suited to theparticular use contemplated.

The flow diagrams depicted herein are just one example. There may bemany variations to this diagram or the steps (or operations) describedtherein without departing from the spirit of the invention. Forinstance, the steps may be performed in a differing order or steps maybe added, deleted or modified. All of these variations are considered apart of the claimed invention.

The descriptions of the various embodiments of the present inventionhave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to best explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

What is claimed is:
 1. A method of making a semiconductor device, themethod comprising: patterning a fin in a substrate; forming a gatebetween source/drain regions over the substrate, the gate having adielectric spacer along a sidewall; removing a portion of the dielectricspacer and filling with a metal oxide to form a spacer having a firstspacer portion and a second spacer portion; forming a source/draincontact over at least one of the source/drain regions; recessing thesource/drain contact and forming a via contact over the source/draincontact; and forming a gate contact over the gate, the gate contacthaving a first gate contact portion contacting the gate and a secondgate contact portion positioned over the first gate contact portion;wherein the first spacer portion isolates the first gate contact portionfrom the source/drain contact, and the second spacer portion isolatesthe second gate contact portion from the source/drain contact.
 2. Themethod of claim 1, wherein the metal oxide is hafnium oxide (HfO₂),aluminum oxide (Al₂O₃), or a combination thereof.
 3. The method of claim2, wherein the spacer is positioned over the gate.
 4. The method ofclaim 1, wherein the second gate contact portion is wider than the firstgate contact portion.
 5. The method of claim 1, wherein the spacer has aheight in a range from about 5 to about 70 nanometers (nm).
 6. Themethod of claim 1, wherein filling with the metal oxide is performed byan atomic layer deposition process.
 7. The method of claim 1, whereinthe dielectric spacer comprises SiN, SiOCN, SiBCN, or any combinationthereof.
 8. The method of claim 1, wherein recessing the source/draincontact is performed to a depth in a range from about 5 to about 40 nm.9. A method of making a semiconductor device, the method comprising:patterning a fin in a substrate; forming a gate between source/drainregions over the substrate, the gate having a dielectric spacer along asidewall; removing a portion of the dielectric spacer and filling with ametal oxide to form a spacer, the spacer having a first spacer portionand a second spacer portion; recessing the gate and depositing adielectric cap over the gate; forming a source/drain contact over atleast one of the source/drain regions, the source/drain contactcontacting the spacer and the dielectric spacer; forming a via contactover the source/drain contact; and removing the dielectric cap andforming a gate contact over the gate, the gate contact having a firstgate contact portion contacting the gate and a second gate contactportion positioned over the first gate contact portion; wherein thefirst spacer portion isolates the first gate contact portion from thesource/drain contact, and the second spacer portion isolates the secondgate contact portion from the source/drain contact.
 10. The method ofclaim 9, wherein the spacer is over a portion of the dielectric cap. 11.The method of claim 9, further comprising recessing the source/draincontact to form a recess before forming the via contact to a depth in arange from about 30 to about 150 to form a source/drain recess.
 12. Themethod of claim 11, further comprising depositing an oxide layer to fillthe recess, patterning the oxide layer to form a via contact patternover the source/drain contact, and filling the via contact pattern witha conductive metal to form the via contact.
 13. The method of claim 9,further comprising depositing an oxide layer over the gate, patterningthe oxide layer to form a gate contact pattern, and filling the gatecontact pattern with a conductive metal to form the gate contact. 14.The method of claim 9, wherein filling with the metal oxide to form thespacer is by an atomic layer deposition process.
 15. A semiconductordevice, comprising: a fin patterned in a substrate; a gate contactdisposed over a gate positioned over the substrate, the gate contacthaving a first gate contact portion contacting the gate and a secondgate contact portion positioned over the first portion; a source/draincontact disposed over a source/drain region positioned over thesubstrate; and a spacer between the source/drain contact and the gatecontact, the spacer having a first spacer portion that isolates thefirst gate contact portion from the source/drain contact and a secondspacer portion that isolates the second gate contact portion from thesource/drain contact.
 16. The semiconductor device of claim 15, whereinspacer comprises a metal oxide.
 17. The semiconductor device of claim16, wherein the metal oxide is HfO₂, Al₂O₃, or a combination thereof.18. The semiconductor device of claim 15, wherein the gate contactcomprises Al, Pt, Au, W, Ti, or any combination thereof.
 19. Thesemiconductor device of claim 15, wherein the second gate contactportion is wider than the first gate contact portion.
 20. Thesemiconductor device of claim 15, wherein the spacer has a height in arange from about 5 to about 70 nm.